WASHINGTON -LRB- CNN -RRB- -- When shots rang out at the U.S. Holocaust Memorial Museum last week , security officers Harry Weeks and Jason McCuiston were stunned .

Harry Weeks , left , and Jason McCuiston fired on James von Brunn at the Holocaust Memorial Museum .

`` I would say it was surreal , both of us could n't believe what was happening , '' Weeks told CNN in his first national televised interview since the June 10 shooting . `` I know myself I just , I heard ` pop , pop ' and it was surreal . ''

McCuiston added : `` It was n't normal . You knew something was wrong and you knew it was very bad . ''

What went terribly wrong is that white supremacist James von Brunn allegedly walked into the museum and started firing his rifle , shooting security officer Stephen Johns in the chest .

Despite their initial shock , Weeks and McCuiston kept their composure enough to draw their weapons and start shooting at von Brunn , 88 .

Weeks had fired his gun in the line of duty 25 years earlier as a Washington , D.C. , police officer . But he said nothing compared to this bloody confrontation .

`` This was terrible , '' Weeks said softly . `` This was worse . ... We lost Officer Johns . ''

Johns died shortly after the shooting , leaving behind a family that includes a teenage son who told CNN affiliate WUSA-TV the day after the tragedy that his dad was `` my hero . ''

Watching a video clip of those comments , McCuiston started crying . `` First thing I thought about , I have an 11-year-old , '' the officer said before breaking down . Watch the officers tell their story ''

Just moments before their joint interview with CNN on Thursday , McCuiston and Weeks attended a grief counseling session together , and both men say they are still struggling with their emotions .

The security officers said they believe von Brunn will survive his wounds and eventually face trial . So they would not discuss details of the shootout out of a fear of jeopardizing the criminal investigation , but they were willing to discuss their memories of Johns so that the public knows more about him .

McCuiston said the 6-foot-6-inch , 300-pound Johns was a `` gentle giant '' who was always friendly to colleagues and museum visitors . `` Just an awesome guy , '' he recalled . `` Grin from ear to ear . You 'd never know that man probably ever had a bad day in his life . ''

Weeks said he wanted the world to see `` what a man of hate did to this family , and the grief he caused . Let 's all remember Officer Johns , and his family , because he took the ultimate -- he did his job and he was where he was supposed to be -- and the family suffered . That could have been anyone . ''

McCuiston and Weeks , however , deflected suggestions that they may be heroes as well because if they had not stopped von Brunn , there 's no telling how many of the more than 2,000 people visiting the museum at the time could have been injured or killed .

`` A lot of people are going to be saying what they have been saying , ` You are a hero , you 're this , you 're that , ' '' McCuiston said . `` It 's like we tell everybody , ` We chose this job , it 's a job . It 's the same as a firefighter who would walk into a building , that is his job , he chose to do it . ' ''

Johns ' funeral on Friday has been moved to a larger church in the Washington area to accommodate all of the people who want to attend , and the museum will be closed most of the day so that his colleagues can attend .

`` Everyone knows when you lose someone , death is one of the worst things , even though it is reality , '' McCuiston said . `` Time will hopefully heal all , and hopefully there will be a little bit of closure with us and the family and we can all just move forward but never forget what a wonderful man he was . ''

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Security officers Harry Weeks and Jason McCuiston recall shooting , fellow officer

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When they heard shots at museum , they knew something had gone terribly wrong

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They call slain officer a `` gentle giant '' who was always friendly to colleagues , visitors

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Men , who shot shooting suspect , say they 're not heroes , were just doing their jobs